Data/hora: 01/06/2024 02:10:54

Provedor de dados: | 56
País: | Brazil
Título: | Effect of calcium intake on urinary oxalate excretion in calcium stone-forming patients
Autores: | Nishiura,J.L.; Martini,L.A.; Mendonça,C.O.G.; Schor,N.; Heilberg,I.P.
Data: | 2002-06-01
Ano: | 2002
Palavras-chave: | Calcium; Hypercalciuria; Hyperoxaluria; Kidney stones; Oxalate.
Resumo: | Dietary calcium lowers the risk of nephrolithiasis due to a decreased absorption of dietary oxalate that is bound by intestinal calcium. The aim of the present study was to evaluate oxaluria in normocalciuric and hypercalciuric lithiasic patients under different calcium intake. Fifty patients (26 females and 24 males, 41 ± 10 years old), whose 4-day dietary records revealed a regular low calcium intake (&lt;=500 mg/day), received an oral calcium load (1 g/day) for 7 days. A 24-h urine was obtained before and after load and according to the calciuria under both diets, patients were considered as normocalciuric (NC, N = 15), diet-dependent hypercalciuric (DDHC, N = 9) or diet-independent hypercalciuric (DIHC, N = 26). On regular diet, mean oxaluria was 30 ± 14 mg/24 h for all patients. The 7-day calcium load induced a significant decrease in mean oxaluria compared to the regular diet in NC and DIHC (20 ± 12 vs 26 ± 7 and 27 ± 18 vs 32 ± 15 mg/24 h, respectively, P&lt;0.05) but not in DDHC patients (22 ± 10 vs 23 ± 5 mg/24 h). The lack of an oxalate decrease among DDHC patients after the calcium load might have been due to higher calcium absorption under higher calcium supply, with a consequent lower amount of calcium left in the intestine to bind with oxalate. These data suggest that a long-lasting regular calcium consumption &lt;500 mg was not associated with high oxaluria and that a subpopulation of hypercalciuric patients who presented a higher intestinal calcium absorption (DDHC) tended to hyperabsorb oxalate as well, so that oxaluria did not change under different calcium intake.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002000600006
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2002000600006
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.35 n.6 2002
Fonte: | info:eu-repo/semantics/openAccess